Looper operating mechanism for sewing machines



March 22, 1932. ZEIER AL i 1,850,949

LobPER OPERATINGMECHANISM FOR SEWING mcnmss Filed Au i' 27, 1928 s Sheets-Sheet 1 W TN i. Er,

ill in I March 22, 1932. I z R ET L 1,850,949

LOOPER OPERATING MECHANISM FOR SEWING MACHINES Filed Aug. 27,1928 5 Sheets-Sheet 2 'March 22, 1932. F. F. ZEIER ET AL 1,850,949

I LOOPER OPERATING MECHANISM FOR SEWING MACHINES Filed Aug. 2'7, 1928 3 Sheets-Sheet 3 Patented Mar. 22, 1932 UNITED "STATES PATENT FFICE FREDERICK F. ZEIER AND CLARENCE C. SMITH; OF CHICAGO, ILLINOIS, ASSIGNORS 'I'O UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS LOOPER OPERATING -MEC1IANISM FOR SEWING MACHINES Application filed August 27, 1928. Serial No. 302,229..

The invention relates to new and useful improvements in sewing machines, and more particularly to a looper operating mechanism for a sewing machine.

An object of the invention is to provlde a looper operating mechanism wherein the looper ispositively moved into and out of the needle thread loop by a train of mechanism'wherein the parts are positively actuated and positively connected and are su stanti ally free from adjustment.

A further object of the invention is to provide a looper mechanism of the above type with means whereby the looper may bemoved to a position where it is readily accessrblefor threading without actually disconnecting the looper from the actuating mechanism therefor.

In the drawings 2-- Figure 1 is a plan view of a part of the machine beneath the cloth plate showing one embodiment of the invention;

Fig. 2 is a front view of the parts beneath the cloth plate showing the looper at the rear end of its stroke;

Fi 3 is a view similar to Fig. 2 but showing t e looper as moved to a position fo threading; i

Fig. 4 is a sectional view on the line 1-4 of Fig. 1.

Fig. 5 is a plan view of the rock shaft and the intermediate parts operated therewith for oscillating the looper.

The invention is directed to animprovement in a looper operating mechanism for asewing machine. The looper is mounted for oscillation on a rocker and is oscillated into and out of the needle thread loop by a link which is connected to a rock shaft which in turn is connected to an eccentric strap actuated by an eccentric on the main shaft. All of the parts are located beneath the cloth plate. This rock shaft is an integral structure having one projecting arm which is conneoted to the link and another arm which is connected to the eccentric strap. The rock I shaft is in the form of a sleeve fixed to a shaft which is mounted for oscillation in spaced bearings, and the sleeve fits between the bearings so as to prevent undue-endwise movement of the rock shaft. The link which con nects the looper shaft to the looper is formed in two sections, which are pivoted together with the end of one sect on projecting beyond the pivot. A sleeve fitting on the link is yieldingly held so as to cover the connections and hold the parts ina straight line. By moving the sleeve endwise of the link the link may be buckled to move the looper to a position for threading. The rocker on which the looper is mounted is oscillated for giving the looper a needle avoiding movement by means of an arm which is attached to a short shaft connected to the rocker, and this arm is located directly above the rock shaft which oscillates the looper. i

Referring more in detail to the drawings, the machine as shown includes a supporting bed 1. A main shaft 2 is mounted for rota.- tion in suitable bearings carried by the bed.

The looper is indicated at 3. The looper is.

mounted on a carrier 4, which is pivoted at 5 to a looper rocker 6. The looper is oscillated on its pivot andmoved into and out of the needle thread loop by means of a link 7, which is pivoted at 8 to the looper carrier and at 9 to the oscillating arm 10 carried by a rock shaft. The rock shaft includes a sleeve 11, which is secured to a shaft 12, and the shaft 12 is mounted for oscillation in the bearing lugs 13 and 14. A sleeve extends substantially from one lug to the other, and thus it is that the rock shaft is held from endwise movement. On the end of the shaft there is a collar-15 which'is secured to the shaft and further holds the shaft from any inward movement. The arm 10 is integral with the sleeve 11. The sleeve 11 is also provided with an integral arm 16. This arm 16 carries a ball stud 17. An eccentric strap 18 cooperating with an eccentric 19 on the main shaft 2 engages this ball stud, thus it is that the eccentric strap oscillates the rock shaft outer end of the shaft 20 is journaled in a bracket 23 carried by the bed of the machine. By placing the forked arm for oscillating the looper rocker directly over the rock shaft which oscillates the looper, a very compact arrangement of the parts is provided. By making the rock shaft in the form of a sleeve with integral arms there are no adjustments to be made or to work loose during the operation of the machine. These arms are placed in the proper fixed relation to the shaft in the manufacture of the machine.

The link 7 for oscillating the looper is made in two sections 24 and 25 which are pivoted at 26. The part 24 is forked, and the part 25 projects between the forks. A knurled sleeve 26a surrounds this link and is held by means of a spring 27 forced against the shoulder 28 on the link and in this position the sleeve surrounds the pivoted connection between the parts. The sleeve has a sliding lit with the link and when moved to the position so as to enclosethe pivotal connection it holds the parts in alinement. This is the normal position of the parts for the actuation of the looper into and out of the needle thread loop. lVhen the machine is stopped with the looper fully retracted, the sleeve may be moved so as to uncover the pivotal connection between the parts and the link can be buckled or collapsed, the parts swinging on each other, and this will cause the looper to be further retracted from be neath the throat plate so that it is readily accessible for threading. After the looper has been threaded and moved back into its working position and as soon as the parts of the link are brought into alinement the spring will automatically move the sleeve over the pivotal connection and thus bring about a normal rigid condition for the connecting member.

From the above it will be apparent that we have provided a looper mechanism wherein the looper is moved into and out of the needle loop by a train of mechanism wherein the parts are positively actuated and positively connected and the oscillating rock shaft which is a part of the train of mechanism is one integral structure. This provides a very efficient looper operating mechanism which may be operated at hi h speed without any of the parts working loose, and furthermore it provides a construction wherein there is no danger of the parts being shifted and thus an improper timing of the looper obtained. Furthermore, by the above looper mechanism the looper may be readily positioned for threading without disturbing its operating connection to the actuating means therefor.

It is obvious that minor changes in the details of construction may be made without departing from the spirit ofthe invention as set forth in the appended claims.

Having thus fully described our invention what we claim as new and desire to secure by Letters Patent, is

1. A looper mechanism for sewing machines including a looper, a looper rocker, means for oscillating the looper rocker, and means for oscillating the looper on the rocker into and out of the needle thread loop comprising a shaft, an eccentric thereon, a rock shaft having integral arms projecting therefrom, an eccentric strap cooperating with the eccentric and'connected to one of said arms, a link connected to the other arm and to the looper for oscillating the same, said link being formed in two parts pivoted together, and shiftable means for holding said parts in alinement.

2. A looper mechanism for sewing machines including a looper, a looper rocker, means for oscillating the looper rocker, and

means for oscillating the looper on the rocker into and out of the needle thread loop comprising a shaft, an eccentric thereon, a rock shaft having integral arms projecting therefrom, an eccentric strap cooperating with the eccentric and connected to one of said arms, a link connected to the other arm and to the looper for oscillating the same, said link being formed in two parts pivoted together, a sleeve surrounding the link and adapted to engage over said pivoted parts for holding the parts in alinement, and a spring surrounding the link and bearing against the sleeve for normally holding the sleeve so as to enclose the pivoted parts.

8. A looper mechanism for sewing machines including a looper, a looper rocker, means for oscillating the looper rocker, and means for oscillating the looper on the rocker into and out of the needle thread loop comprising a shaft, an eccentric thereon, a rock shaft consisting of a sleeve, arms integral therewith, a shaft passing through said sleeve and supporting the same, an eccentric strap cooperating with the eccentric and connected to one of said arms, a link connected to the other arm and to the looper for oscillating the same, said link being formed in two parts pivoted together so that said parts when buckled will position the link where it may be readily threaded, a sleeve surrounding the link adapted to engage over said pivoted parts for holding the parts in alinement, and yielding means for holding the sleeve so as to enclose the pivoted parts.

4. A looper mechanism for sewing machines including a looper, a looper rocker, a main shaft, a forked arm connected to said looper rocker, an eccentric on the main shaft with which said forked arm cooperates, a rock shaft located beneath said forked arm consisting of a sleeve, a shaft to which said sleeve is attached, supporting bearings for said shaft, said sleeve having an integral horizontally projecting arm and an integral vertically projecting arm, a second eccentric on the main shaft, an eccentric strap cooperating therewith and connected to said horizontal arm for oscillating the rock shaft, a link connecting the vertical arm of the rock shaft to the looper for oscillating the looper, said link being formed in two parts pivoted together, a sleeve surrounding the link and adapted to enclose said pivoted parts for holding the parts all in alinement, and a spring for holding said sleeve so as to enclose said pivoted parts, said pivoted parts being adapted to swing relative to each other when the sleeve is retracted from enclosing the pivotal connection for the said parts for positioning the looper so that it may be readily threaded.

5. A looper mechanism for sewing machines including a main shaft, a looper, means for actuating said looper from said shaft, said means including pivotally connected members adapted to be buckled whereby the looper may be rendered accessible for threading and returned to the same timed position relative to the looper actuating means, and means carried by said members adapted to hold said pivoted members in rigid position relative to each other for actuating said looper.

6. A looper mechanism for sewing machines including a main shaft, a looper, means: for actuating said looper from said shaft, said means including pivotally connected members adapted to be buckled whereby the looper may be rendered accessible for threading, means carried by said members adapted to hold said pivoted members in rigid position relative to each other for actuating said looper, said last named means including a sleeve slidable over the pivotal connection, and a spring for moving said sleeve over said pivotal connection.

7 A looper mechanism for sewing machines including a main shaft, a looper, means for actuating said looper from said actuating shaft including pivotally connected members adapted to be buckled for moving said looper to render it accessible for threading, automatic means for holding said members in alinement manually operable for releasing said members so that they may be buckled.

In testimony whereof, we aflix our signatures.

FREDERICK F. ZEIER. CLARENCE C. SMITH. 

